


you’re hotter than a bunsen burner set to full power

by sunshine_kitcat (moonkevin)



Category: The Boyz (Korea Band)
Genre: 5+1 Things, Domestic Fluff, Established Relationship, Fluff, Friends to Lovers, Getting Together, M/M, Polyamory, Science, Self-Discovery, but hes dumb, chanhee may be a science major
Language: English
Status: Completed
Published: 2020-09-06
Updated: 2020-09-06
Packaged: 2021-03-06 19:55:04
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,085
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26324491
Author URL: https://archiveofourown.org/users/moonkevin/pseuds/sunshine_kitcat
Summary: 5 science laws Chanhee uses to solve his very non-scientific problem and the answer to all of his problems(Alternatively, Choi Chanhee discovers polyamory in between vectors, broken hourglasses, springs, twin-star systems, quantum entanglement and the conservation of energy)
Relationships: Choi Chanhee | New/Ji Changmin | Q/Kim Younghoon
Comments: 24
Kudos: 141





	you’re hotter than a bunsen burner set to full power

**Author's Note:**

  * For [jenomeow](https://archiveofourown.org/users/jenomeow/gifts).



> Good luck on your hectic schedule isis, this one's inspired by you.

_0\. Every problem can be solved. The only matter is how._

Choi Chanhee would like to think his life is logical and straightforward, for the most part. With a degree in astrophysics pending and the most mundane lifestyle possible, Chanhee prides himself on being able to control and make sense of the turbulent world that is adult life. He’s not a control freak, per se, but Chanhee at least had to be able to understand everything.

On the flip side, of course, is Ji Changmin. Best friends since Changmin saved Chanhee from stepping on a pile of legos back in kindergarten, Chanhee would like to keep Changmin as the chaos factor in his life. Changmin is as random and illogical as it gets, between a fascination for horror movies and a penchant for playing ungodly amounts of pranks on Chanhee and their friends. He grew to become less of a pin in the ass, but more of soft kisses and gentle sunlight on a pretty morning for Chanhee to wake up to. In the grand scheme of things, moments like these are the opposite of rational as Chanhee ditches any thought of his mountains of homework to spend time kissing and cuddling with Changmin until noon. All in all, chaos factors are manageable. They’re inevitable, after all, and Changmin is the best possible factor Chanhee could have asked for.

Which brings them to Chanhee’s new dilemma: Kim Younghoon.

“I’m going to kill you one of these days, Ji Changmin,” Chanhee hisses, rubbing the soles off his foot as Changmin cackles over by the kitchen island. Legos litter the ground, little bricks of death that rival the venom dripping from Chanhee’s eyes.

“You’re being dramatic, Hee,” Younghoon chuckles, starting to clear away the legos to reach him. Chanhee pouts, brows furrowed. Where Ji Changmin had a method to his madness, pranks somewhat predictable after a few times, Younghoon was simply… random. Case in point: he’ll gladly help Changmin set up the death floor for Chanhee, but he’ll also be the one to clean up and pick Chanhee up towards the sofa.

“When’s your date, by the way?” Changmin suddenly calls out from the kitchen, slowly starting to pick up the legos. Younghoon hums, eyebrows scrunched up in thought. Chanhee snorts at him.

“It’s in fifteen minutes, dumbass,” Chanhee deadpans, watching Younghoon’s eyes widen in panic as he runs down the hallway of their tiny two-bedroom apartment. After their shitty landlord raised the price of their cozy home, Chanhee’s life-long experiment with emotions had hit its first snag: capitalism. They couldn’t keep up with payments with just the two of them, so a solution had to be found. Younghoon was the econ major who was also a close friend of Chanhee since sharing a ridiculous amount of math classes together. Tall, gentle and handsome, the beagle-like Younghoon seemed to be the perfect fit to Chanhee’s and Changmin’s dynamics. After all, he was the only one they could find who didn’t mind being sexiled every other week.

The problem is, Chanhee’s previously controlled experiment had a new problem now, and this new chaos factor had no predictable effect on Chanhee himself. Younghoon is a friend, that much is sure. But how much more is Chanhee’s heart trying to strive for?

“I never knew you kept tabs on Hoonie’s schedules. You’re whipped, aren’t you?” Changmin teases once Younghoon has practically barrelled out of the door. Chanhee’s cheeks dust pink as he glares at Changmin, scrunching up his nose.

“It’s not a crush,” Chanhee retorts, “I’m literally dating you.”

Changmin smiles, half-fond, half-teasing as he drops the last of the legos back into their bucket. Chanhee wonders where he even _got_ them.

“The answer to all of your problems is right in front of you, Hee. Aren’t you supposed to be the smart one in this relationship?”

_1\. Vector Addition: Transform the second vector so that its tail is now on the head of the first vector. Their added vector is the vector from the tail of the first to the head of the second_.

If Chanhee had to describe his entire romantic experience in a google document, it’d be limited to two headers and one page, max.

The first header is Changmin, who was simultaneously his first kiss and his first romantic slap. They’ve been friends since forever, and Changmin probably knows more about this irrational demon called ‘emotions’ inside of Chanhee better than Chanhee does himself. So when Changmin laughed at Chanhee’s world shattering breakthrough that he is, in fact, in love with his best friend, Chanhee had promptly slapped him on the arm. Changmin kissed him after, which made up for it, but the slap was well-deserved.

The second header is Kim Younghoon, and the only effect Younghoon has on his emotions demon Chanhee can describe is ‘hammering’. Where Chanhee’s love for Changmin is soft and familiar like a sip of his favourite hot chocolate, Younghoon feels like downing seven shots of alcohol. He’s dizzying and unpredictable, like a storm to Chanhee’s life. Where Changmin is like one vector with a constant angle and distance, Younghoon feels like a million vectors in more dimensions than Chanhee can count. He came before Chanhee and Changmin’s shared vector could reach its destination, spiking their simple and manageable 2D layout into something… unpredictable.

“How’d the date go?” Chanhee asks between bites of takeout, watching out of the corner of his eye as Younghoon drags himself through the door, tossing his coat haphazardly onto the couch.

“Terrible,” Younghoon laments, “mother has terrible taste in guys. If I have to meet another goddamn politics major I’m gonna strangle someone. Just _talking_ to them makes me lose brain cells.”

Changmin snorts, almost spitting out his noodles before flashing Younghoon a sympathetic smile.

“‘Least you got jjajangmyeon!” Changmin points out, sliding a box of takeout towards the only empty stool on the kitchen island. Younghoon sits down with a sigh, grabbing his chopsticks and starting to inhale the food as Chanhee resists the urge to coo at how adorable he is with a noodle stuck right above his mouth. Changmin snorts.

“Moustache,” Chanhee points out in the fondest voice possible. Younghoon cocks his head, confused before Chanhee rolls his eyes.

“You got a little something here,” Chanhee reiterates, watching as Younghoon’s eyes widen in realization.

Observation: the emotions demon thinks that was cute.

Analysis: anything Younghoon does is cute.

Conclusion: Chanhee might be whipped.

“I think I like him,” Chanhee whispers, hesitant as he watches Younghoon carry their dishes to the sink. Changmin sighs and smiles fondly at Chanhee, leaning over the kitchen island to peck his forehead.

“See? He’s not _that_ complex.”

At the end of the day, Chanhee supposes, even an infinite amount of vectors can become one simple arrow from his starting point to his happy ending. Younghoon is an enigma, sure, but even the world’s greatest mysteries can be explained. So what if Chanhee’s experiment hit a snag along the road?

He’ll end up where he needs to end up, regardless of the copious amount of turns.

_2\. The Second & Third Laws of Thermodynamics: The amount of uselessness in a system only grows; but it isn’t infinite. _

The enemy of science is emotions, and Chanhee can’t help but wonder why it has to be that way.

“You’re absolutely irrational, Min!” Chanhee yells, anger flushed in his cheeks as he explodes. Changmin glares at him, eyes filled with frustration as he throws his hands into the air.

“I’m the irrational one?! You’re the one who’s yelling at me for forgetting my toast in the toaster!” Changmin argues, jumping out of his seat as he inches closer to Chanhee. Chanhee growls.

“You never fucking do anything around here and chalk it up to what, forgetfulness? I’m not your fucking maid, Min! Get your own fucking toast and get it out of the goddamn toaster!” Chanhee explodes, yelling at max volume. Younghoon is just in the living room, watching them argue with an expression of concern.

“You’re the neat freak who refuses to calm down for three seconds!” Changmin retorts, “stop getting on my case! I don’t even know why I put up with you!”

Chanhee’s eyes widen, feeling the familiar prick of tears in the corner of his eyes. He refuses to let them slip for the cruel jerk that is Changmin.

“Then don’t put up with me!” Chanhee screams, pushing Changmin away from him, “you can get lost for all I care!”

The rational part of Chanhee knows he’s just stressed from finals breathing down his neck, but at the same time, he’s too angry to even care at this point. He storms out of the kitchen and locks himself in the bathroom. As soon as the click of the lock rings in the air, Chanhee breaks, hot tears spilling as the back of his head hits the door and his body slides down.

The amount of entropy in a working system only ever grows, Chanhee muses, meaning there is less and less energy to use as time grows on. Time wears down even the brightest of sparks, like a leaking hourglass slowly running out of sand to run. They all break at some point, but that doesn’t mean it hurts any less.

“Hee? You okay?” Younghoon’s voice calls out from behind the bathroom door and Chanhee just falls aparts a little faster. Maybe the break had been happening all this time and he neve realized it. Without letting him know, his heart had found another soul to yearn for, after all.

“I don’t want him to leave,” Chanhee whispers shakily, tears streaming down his cheeks, “I don’t want him to forget me.”

Younghoon sighs on the other side of the door, tapping it gently. Chanhee doesn’t budge, giving Younghoon a silent signal he wants to be left alone.

“He’s not going to leave you, Hee,” Younghoon reassures him gently, “he’s just stressed, like you. If he did, I’ll be the first to punch him, promise.”

A soft, broken giggle tumbles from Chanhee’s lips, melting with the simultaneous fondness and heartbreak in his heart. He still loves Changmin, Chanhee realizes, still willing to spend every last fibre of his finite being on the complicated machine that is their relationship.

“Does he even love me anymore?” Chanhee questions out loud, daring to challenge an assumption he thought was a given truth in his life experiment. Younghoon is silent on the other end, as if disappearing and Chanhee thinks he might just break again.

Still shaking, Chanhee stands up and weakly opens the door, hoping to sneak into his room and be left alone. Instead, he’s greeted with a teary-eyed Changmin being strong armed into the hallway by Younghoon, who looks like he’s about to strangle both of them.

“Y-you idiot!” Changmin screams, anger and heartbreak in his tone as he charges at Chanhee, wrapping him in one big hug. Chanhee startles, instinctively wrapping his arms around Changmin’s torso and squeezing him. He didn’t leave. Changmin didn’t leave.

“Of course I still love you,” Changmin sobs into the crook of Chanhee’s neck, hot and wet tears dripping onto Chanhee’s shirt. Chanhee himself is holding onto Changmin like a lifeline, determined not to let him leave.

“We’re in this together,” Changmin whispers, “and that means I’m going to love you until the day I die.”

Observation: Chanhee and Changmin have had a grand total of seven major fights where a breakup was a genuine concern, and Younghoon was there to diffuse each and every one of them.

Analysis: A machine will eventually run out of energy to function, unless it’s connected to another power source.

Conclusion: Maybe Younghoon had a bigger role in Chanhee’s emotional experiment than Chanhee initially realized.

“Don’t you get tired? Having to help us make up every time we fight?” Chanhee asks Younghoon that night, as he catches him coming out of the shower. Younghoon shakes his head and smiles softly, dripping wet hair gleaming under the light like he’s some kind of relationship guardian angel.

“At this point, I’m just as invested in this relationship as you two are,” Younghoon jokes.

Chanhee files the undertone of yearning in Younghoon’s words as his own imagination. Younghoon is just a really good friend. Nothing more, nothing less.

_3\. Hooke’s Law: The extension of a spring is proportional to its tension._

Some days, Chanhee thinks his brain is going to try too hard trying to understand the phenomena that is having a crush _and_ a boyfriend, he’ll just explode.

And today, Younghoon is doing absolutely nothing to help with that.

“Smells good,” Younghoon whispers, nose buried into Chanhee’s hair as he startles Chanhee out of scowling at his homework like it’ll magically complete itself. Chanhee shifts his weight on his bed, trying to turn to Younghoon when Younghoon places a hand over his chest and pushes Chanhee back down. Younghoon himself is also on the bed, one arm thrown over Chanhee’s chest and one grabbing Chanhee’s fallen textbook.

“Why are you sniffing my hair?” Chanhee asks, thoroughly confused. Younghoon shakes his head.

“No reason,” he responds happily. Chanhee noticed his new clinginess a few days ago, when Younghoon had draped himself over a sleepy Changmin as they both dozed off on the living room carpet. Ever since Younghoon’s last blind date, courtesy of his lovely but frankly clueless mother, he’s been in another sad slump, as if moping the loss of a potential lover. A part of Chanhee somehow wishes he never finds success with the blind dates so Younghoon remains an everlasting constant in Chanhee and Changmin’s lives. He quickly chides himself. Younghoon deserves happiness as much as he gives Chanhee happiness. The best course of action is simply to let Younghoon find love on his own.

“And what about your buried feelings?” Changmin asks one day, interrupting Chanhee mid rant. They’re in the kitchen again, the central place of activity in their household due to the copious amount of food they consume. Chanhee slams the cupboard shut a little too forcibly, pursing his lips.

“It’ll be fine,” Chanhee muses, trying to convince himself more than anything. Changmin raises a brow.

“Hasn’t Hoonie made you watch enough romcoms for you to know that that’s never a good idea?” Changmin points out. Chanhee shrugs again, but his brain is starting to whir again. He supposes crushes are like a spring. Wound them up too tight and hide them, and all one does is make the spring practically explode later on.

“I can’t just walk up to him and go ‘hey, guess what? I have a crush on you _and_ I still love my boyfriend too!’,” Chanhee points out, rolling his eyes. Changmin sighs, waving his fork in the air.

“Chanhee I am literally begging you to just google polyamory right now,” Changmin deadpans. Chanhee scrunches up his eyebrow, thoroughly confused.

“Polyamory means that everyone in the relationship loves each other, Min,” Chanhee frowns, “and even if Hoonie liked me back, what about you—“

Chanhee stops, the spring finally reaching its release point as he puts two and two together, his brain shutting down completely as everything explodes.

“Oh my god, you like him too!” Chanhee exclaims, jabbing a finger at Changmin accusingly. Changmin just rolls his eyes.

“Finally. I was starting to lose hope.”

Observation: Changmin had been the one to propose Younghoon moving in with them in the first place, despite Chanhee being Younghoon’s direct friend. He was also the one overly eager to invite Younghoon into their routine, integrating his preferences into their domestic dance.

Analysis: Chanhee had always been worried about accidentally switching partners. But then again, there are plenty of dances for three people.

Conclusion: Perhaps, maybe he never had to think so hard about this.

_4\. Kepler’s Third Law: the square of a planet’s orbital period is proportional to the cube of the semi-major axis of its orbit._

“How does a three-person relationship even work?” Chanhee wonders aloud, a half eaten dumpling on his fork. Changmin downs a glass of orange juice and hums.

“I can’t think of any reason it should be any different than a two person relationship,” Changmin points out, to which Chanhee frowns at.

“There’s a world of difference!” Chanhee argues, “there’s another whole person to consider! What if you loved one person more or one person less? What if you’ve been so enamoured with one you forget the other? Heck, even cuddles are more complex now! How does two little spoons and a big spoon even work?!” Chanhee rambles listing things off of his fingers. Changmin rolls his eyes, reaching over and shoving the rest of Chanhee’s dumpling into Chanhee’s half-open mouth before pecking him lightly on the nose.

“At the end of day, Hee, it’s just love. If you truly love someone and they love you back, you can make anything work,” Changmin reassures him, rubbing Chanhee’s knuckles comfortingly. Chanhee sighs.

Changmin and Younghoon are like twin stars in Chanhee’s system. Dual-star systems are unstable and mysterious, to say the least, two giant bodies of mass and energy fighting for dominance like siblings arguing for the best piece of toast in the morning. They resemble the two opposing corners of Chanhee’s mind, not knowing who he _actually_ likes. The answer used to always be Changmin, but Younghoon is relentless in his presence on Chanhee's mind.

Chanhee hums as he twirls his pencil around, trying to focus as his thoughts drift elsewhere. Without thinking, his feet props him up as he walks over to Younghoon’s room. Changmin and Younghoon and laughing and cuddling, talking about god knows what and Chanhee finally realizes the kind of twin-star system they are. Perfectly in balance, reaching a point of coexistence so powerful it’s as if they were simply an extension of one really big system.

Observation: At some point, it no longer mattered how many people are in Chanhee’s heart because at the end of the day, he loved them both to the ends of the infinite universe.

Analysis: Kepler’s third law of Orbital Motion: the square of a planet’s orbiting planet is proportional to the cube of the semi-major axis.

Conclusion: Chanhee’s fourth law of Emotions: two lifetimes of love is proportional to three people in love. Essentially, there is no difference.

“Are you just going to stand there?” Changmin calls out, snapping Chanhee out of his daze. Changmin is wrapped around Younghoon’s back like a koala, one cheek buried in Younghoon’s shoulder while a lazy smile blooms on his face. Chanhee grins, stepping towards the bed as he meets Younghoon’s fond gaze. Without a word, Younghoon opens up his arms and welcomes Chanhee, practically dragging him into bed.

The rational part of Chanhee notes how late it is and how warm Younghoon is. Midnight crickets sing their lullaby outside while Changmin reaches over the bedside table and turns off the lamp, leaving three boys drowning in each other in the comfortable blanket of affection and darkness. Chanhee buries his nose in the crook of Younghoon’s neck, letting his lips ghost over Younghoon’s collarbone. There’s an invisible line he’s toeing at, one that beckons him to leap over and just kiss the pretty boy in front of him. On the other side is Changmin, urging him on as if he crossed the line already, even if not in words.

Changmin is brave where Chanhee is not, however, and no one but the quiet moonlight knows of Chanhee’s first attempt to love the universe.

_5\. Quantum Entanglement: When a group of particles are entangled, its quantum state cannot be described independent from the others’._

And yet, despite Chanhee’s neverending hesitance, something does change. At some point, he learns he can no longer define his relationship with Younghoon as strictly platonic anymore. They haven’t properly kissed, per se, nothing more than stolen forehead kisses here and there. But somehow, the line yet to be crossed seemed to have curved to allow a kind of limbo, as if teasing Chanhee with the possibilities.

Chanhee learns to cook all of Younghoon’s favourites and adds them next to Changmin’s in his notebook with swirly hearts. Younghoon buys them matching animal slippers and onesies under the excuse of early Christmas in September. He could’ve waited, sure, but he had a hunch something else would come up and he’d forget.

Chanhee had nearly teared up over a penguin onesie that day.

Changmin seemed to be the only one with any clue about the real location of this invisible line, jumping from one side to another like it was second nature. One moment he’ll be dragging them both on impromptu dates all over town. The next moment, he’ll be pulling out old polaroids of their adventures to hang up around the place as if the three of them are some kind of sappy couple celebrating their anniversary.

Observation: Before he could realize it, Chanhee supposes their lives have been irrevocably entangled.

Analysis: the Basic Principle of Quantum Mechanics states that the state of an individual particle in a group of entangled particles can’t be described without the others.

Conclusion: Chanhee’s life now consists of two lovers, whether the fact has been spoken about or not.

“Pocky?” Younghoon offers, snapping Chanhee out of his daze. Chanhee blinks at the offered biscuit stick, gingerly reaching out to accept it when Younghoon pulls back suddenly and places the stick between his front teeth. Chanhee flushes, realizing the implications of Younghoon’s actions.

“Are you seriously doing this right now?” Chanhee deadpans, refusing to lean in. Younghoon grins cheekily at him.

“Minnie told me everything,” Younghoon comments, waving Chanhee’s apprehension off, “and I’m just curious what you’re so worried about.”

Chanhee frowns. “He told you… everything? Since when—“

Chanhee stops, recalling the fateful night the line was first revealed to him. Changmin had always been the braver one. Chanhee can’t be surprised Changmin’s crossed the line before he had too.

Before Younghoon can react, Chanhee surges forwards and bites on the Pocky, reducing it to nothing but a stump as Younghoon flinches. Quickly chewing and swallowing the snack, Chanhee grins and leans over once again, dutching every rational thought as he smashes their lips together. 

Fireworks and fireflies tingle at his skin, prickling it like a cool breeze on a hot July afternoon. The pure serotonin and dopamine that runs through his body suddenly spikes, spurring Chanhee onwards as he climbs into Younghoon’s lap for better access. Younghoon tastes like home and an adventure at the same time, relaxing and gentle yet so damn _eager_. His arm loops around Chanhee’s waist, pulling them impossibly close as Chanhee sighs into the kiss.

“Just so you know, this is a shit proposal,” Chanhee mutters. Younghoon laughs loudly, chest vibrating with the action and Chanhee thinks he might absolutely combust if Younghoon somehow got even cuter.

“I love you too, Hee.”

_+1. The Law of Conservation of Energy: Energy is not created nor destroyed—it only changes from one state to another._

In short, Chanhee’s not really sure what his problem really was in the first place. He knows the subject is one mysterious Kim Younghoon, who made Chanhee’s heart beat in a way he thought wasn’t possible for anyone other than Changmin. He hadn’t pegged himself as the type to fall in love with two people, but then again, it really was inevitable.

Observation: Chanhee has two beautiful boys next to him and soft sunlight drifting through the soft cream-coloured blinds. Younghoon is sleeping like a rock, absolutely inanimate save for the soft rise and fall of his chest and a deep rumble of a snore that makes Chanhee giggle. Changmin is awake, exchanging soft morning kisses with Chanhee over top of Younghoon. Whispers of ‘I love you’ hang in the air like a soft wispy cloud on a beautiful autumn day.

Analysis: Energy is not created nor destroyed. It only transforms from one state to another.

Conclusion: Chanhee’s final law of Relationships: Love is not created nor lost, it only changes from platonic to romantic.

“You two are loud,” Younghoon complains, voice raspy and husky from sleep. Chanhee smiles at him, leaning up to place a soft kiss on the tip of Younghoon’s nose.

“You love us,” Chanhee argues. Younghoon hums softly, reaching his hands up to card through both of their hairs at the same time. Changmin preens at the touch, practically squirming as a wide smile blooms on his face.

“And I love you two too.”


End file.
